Snowboarding is a gliding sport in which both feet of the rider are on a single board and positioned obliquely with respect to the longitudinal axis of the board.
There are two origins for shoe/retention device assemblies corresponding to different dominant practices.
For a practice of the alpine type preferably carried out on a trail or packed snow, the shoes are of the alpine or cross-country ski type, rigid, in such a manner to allow for very sustained and precise support transmissions and edge settings. The retention elements cooperating with such shoes are generally stirrups locking each of the front and rear ends of each shoe sole. The rigidity of such shoe is generally obtained by a shell and a collar journalled made of plastic thus constituting a closed power circuit. This construction has the following disadvantages:
hinderance during the transition phases when the rider has only one shod foot on the board and pushes against in the snow with the second foot in order to move, notably on flat or in tendon lines for ski lifts, PA1 hinderance during the movements that are necessary in the practice of snowboarding, particularly when the knee must move inwardly by a lateral flexion of the ankle, either to bend further, or to land from a jump, or to carry out figures during an airborne phase, PA1 filtration of the sensations coming from the board through the rigid sole, thus reducing much of the information circuit, PA1 hinderance during walking. PA1 that the retention device comprises means for attachment in the vertical direction and along a horizontal plane cooperating with complementary shoe attachment means arranged in a central portion of the sole of the shoe, PA1 that the shoe comprises a skeleton constituting a minimal energy circuit for the transmission of forces and support necessary in the practice of the sport, and PA1 that this energy circuit passes through the attachment means of the sole of the shoe.
For a practice of the "Soft" type preferably carried out on soft, non-packed, powdery snow, favoring jumps, sides-lipping, and other figures, the shoes are very flexible and the necessary supports are essentially provided by retention elements in the form of an open shell and a journalled collar that are rigid, associated with straps, two or three per foot, allowing for the transmission of vertical forces from the bottom upward and forward.
Furthermore, the maintaining of the ankle and the instep is obtained by a diagonal strap substantially positioned at the level of the flexion fold and associated with a semi-rigid padded plate that distributes the pressure on the instep and ensures a progressiveness of the flexion of the heel, toward the front in particular.
These flexible shoes are essentially designed as sealed and comfortable shoes and having no role in the transmission of forces.
Therefore, they have the advantage of being comfortable and allowing a normal walk.
On the contrary, the retention elements with a shell are cumbersome and require a precise adjustment to the volume of the shoe during each operation for "putting on" the snowboard.
From the patent application FR No. 93.06006, now French Patent No. 2,705,268, published Nov. 25, 1994, there has been proposed a device for retaining a snowboard shoe on a board by complementarity of the forms between the lower surface of the sole and the retention device, and the device for vertical latching.
Such a retention device has a particularly simple construction and is independent of the size of the shoe.
On the contrary, it requires a rigid sole and is therefore not compatible with shoes of the boot type with a flexible sole.
Such a retention device does not allow either the taking of support, transmissions of forces provided by the retention devices with a shell.